Coach certification

I have been seriously thinking about enrolling for coach certification for several days now. I have the money and time( I work 4 days a week) but I am worried that I will make a fool of myself . In my current profession as a physician , my patients view me as kind and compassionate with excellent communication skills , which is why I think this could work out for me. at the same time ,
I have a lot of insecurity about my voice ( I record myself and feel that I have a soft /meek voice). I am also worried about how I could explain this huge expense to my spouse. If I go thru this, I really do want to be a coach for high achieving medical professionals ( not just incorporate skills into my day to day practice) . I am also shy , and get very uncomfortable in social situations. Part of me wants to be a coach just to prove to myself that I can beat all my insecurities but they are standing in the way of me making a decision . I just don’t know what to do . I feel paralyzed. While I know I am contributing immensely to the world as a subspecialist , I also feel stuck and really want o evolve to a higher potential/version of myself and my job is not doing that for me . I am hoping if you could help me with these thoughts .